But CNBC's Faber says terms of deal with Comcast are nearly ironed out.
Rupert Murdoch's News Corp. and John Malone's Liberty Media Corp. are interested in NBC Universal, CNBC is reporting.
Cable giant Comcast already is in talks with General Electric, parent of NBCU, to buy a controlling stake in the entertainment conglomerate in a deal that would see NBCU 51 percent owned by Comcast and 49 percent by GE.
Now CNBC is saying GE is considering other proposals, including the two media giants, as its partner Vivendi decides what to do with its 20 percent stake in the company. That decision is expected this week.
Meanwhile, CNBC's David Faber says that many of the terms of the Comcast-GE deal have already been negotiated, according to people close to the deal.
Under those terms, GE will have the right to put part of its 49 percent stake in NBC Universal to Comcast after the joint venture has been in existence for three and a half years, and has another put at the seven-year mark, according to people close to the deal.
That deal values NBCU at $30 billion and spins it off into a new company that would be merged with Comcast's content assets and cash.
Analysts see News Corp., which owns the Fox cable network and local TV stations, as a less likely bidder for NBCU because of antitrust concerns.
Liberty Media has been considered a possible bidder for a minority stake; it has a history of taking minority stakes in big media companies.
CNBC and Reuters said representatives for GE, Comcast and News Corp were not immediately available to comment; a spokeswoman for Liberty Media declined to comment.